Techniques to order direction signals during discontinuous reception

Abstract

Techniques are described herein for reordering beams used to transmit reference signals for subsequent beam sweeps of a beam management procedure. Beams used to transmit reference signals may be hierarchically ordered to enable a user equipment (UE) to terminate the beam management procedure early and thereby conserve power while operating in a discontinuous reception mode. A base station may transmit reference signals using a first ordered set of beams as part of a first beam sweep. The UE may transmit feedback information to the base station about the signal quality for at least some of the reference signals. The base station may generate a second ordered set of beams based on the feedback information. The base station may transmit the reference signals using the second ordered set of beams as part of a second beam sweep.

What is claimed is: 
     
       1. A method for wireless communication, comprising:
 receiving, by a user equipment (UE) operating in a discontinuous reception (DRX) mode, a set of reference signals in a first ordered set of beams, the first ordered set of beams comprising at least a first beam and a second beam received in a first order of a beam sweep; 
 identifying a signal quality for a subset of reference signals received by the UE; 
 transmitting feedback information to a base station based at least in part on identifying the signal quality for the subset of reference signals; and 
 receiving the set of reference signals in a second ordered set of beams that is different from the first ordered set of beams, the second ordered set of beams based at least in part on transmitting the feedback information, the second ordered set of beams comprising at least the first beam and the second beam received in a different order of a later beam sweep. 
 
     
     
       2. The method of  claim 1 , further comprising:
 identifying the first beam to be used to communicate a wake-up signal with the UE based at least in part on identifying the signal quality for the subset of reference signals, wherein receiving the set of reference signals in the second ordered set of beams is based at least in part on identifying the first beam. 
 
     
     
       3. The method of  claim 2 , further comprising:
 identifying the second beam to be used to communicate the wake-up signal based at least in part on identifying the signal quality for the subset of reference signals, wherein receiving the set of reference signals in the second ordered set of beams is based at least in part on identifying the second beam. 
 
     
     
       4. The method of  claim 3 , wherein the first beam is received before the second beam in the different order of the second ordered set of beams; and wherein the first beam is adjacent to the second beam in the second ordered set of beams. 
     
     
       5. The method of  claim 3 , further comprising:
 receiving the wake-up signal using the first beam or the second beam during an on-period of the DRX mode of the UE based at least in part on transmitting the feedback information. 
 
     
     
       6. The method of  claim 1 , further comprising:
 ranking the beams of the first ordered set of beams based at least in part on identifying the signal quality for the subset of reference signals, wherein the feedback information is based at least in part on ranking the beams. 
 
     
     
       7. The method of  claim 1 , wherein identifying the signal quality for each signal further comprises:
 identifying a received signal received power (RSRP), a received signal received quality (RSRQ), a signal-to-noise ratio (SNR), a signal-to-interference-plus-noise ratio (SNIR), or a combination thereof for the subset of reference signals. 
 
     
     
       8. The method of  claim 1 , further comprising:
 selecting a beam index of a beam of the first ordered set of beams to be used to communicate a wake-up signal, wherein the feedback information is based at least in part on selecting the beam index. 
 
     
     
       9. The method of  claim 1 , further comprising:
 identifying an angle of departure of the subset of reference signals or a reception array used to receive the subset of reference signals, wherein the feedback information includes information related to the angle of departure or the reception array of the subset of reference signals, wherein receiving the set of reference signals in the second ordered set of beams is based at least in part on identifying the angle of departure or the reception array used to receive the subset of reference signals. 
 
     
     
       10. The method of  claim 1 , wherein the set of reference signals comprises channel state information reference signals (CSI-RSs), demodulation reference signals (DMRSs), primary synchronization signals (PSSs), or secondary synchronization signals (SSSs), or a combination thereof. 
     
     
       11. The method of  claim 1 , wherein the UE is in a connected discontinuous reception (C-DRX) mode, and wherein the set of reference signals are received during an off-period of the DRX mode of the UE. 
     
     
       12. The method of  claim 1 , wherein the UE transmits the feedback information during an on-period of a DRX cycle or during an off-period of the DRX cycle. 
     
     
       13. The method of  claim 1 , wherein a number of reference signals of the subset of reference signals is less than a number of reference signals of the set of reference signals. 
     
     
       14. A method for wireless communication, comprising:
 receiving, by a user equipment (UE) operating in a discontinuous reception (DRX) mode, a set of reference signals in a first ordered set of beams; 
 identifying a signal quality for a subset of reference signals received by the UE; 
 transmitting feedback information to a base station based at least in part on identifying the signal quality for the subset of reference signals; 
 receiving the set of reference signals in a second ordered set of beams that is different from the first ordered set of beams, the second ordered set of beams based at least in part on transmitting the feedback information; and further comprising: 
 configuring a reception array during a gap time between transmissions of the set of reference signals, wherein receiving the set of reference signals in the second ordered set of beams is based at least in part on configuring the reception array during the gap time. 
 
     
     
       15. The method of  claim 14 , wherein the UE configures the reception array during the gap time in response to determining to decode a reference signal of a second beam of the second ordered set of beams subsequent to decoding a reference signal of a first beam of the second ordered set of beams. 
     
     
       16. A method for wireless communication, comprising:
 transmitting a set of reference signals using a first ordered set of beams, the first ordered set of beams comprising at least a first beam and a second beam transmitted in a first order of a beam sweep; 
 receiving feedback information from a user equipment (UE) operating in a discontinuous reception (DRX) mode, the feedback information based at least in part on the set of reference signals; 
 generating a second ordered set of beams for the set of reference signals that is different from the first ordered set of beams, the second ordered set of beams based at least in part on receiving the feedback information from the UE; and 
 transmitting the set of reference signals using the second ordered set of beams in a later beam sweep, wherein transmitting the set of reference signals using the second ordered set of beams comprises transmitting at least the first beam and the second beam in a different order in the later beam sweep. 
 
     
     
       17. The method of  claim 16 , further comprising:
 identifying the first beam of the first ordered set of beams to be used to communicate a wake-up signal to the UE based at least in part on the feedback information. 
 
     
     
       18. The method of  claim 17 , further comprising:
 reordering the first ordered set of beams to prioritize the first beam based at least in part on identifying the first beam, wherein generating the second ordered set of beams is based at least in part on reordering the first ordered set of beams. 
 
     
     
       19. The method of  claim 17 , further comprising:
 identifying the second beam of the first ordered set of beams to be used to communicate the wake-up signal based at least in part on the feedback information; and 
 reordering the first ordered set of beams to prioritize the first beam and the second beam based at least in part on identifying the first beam, wherein generating the second ordered set of beams is based at least in part on reordering the first ordered set of beams. 
 
     
     
       20. The method of  claim 19 , wherein the first beam is transmitted before the second beam in the second ordered set of beams; and wherein the first beam is adjacent to the second beam in the second ordered set of beams. 
     
     
       21. The method of  claim 19 , further comprising:
 transmitting the wake-up signal using the first beam and the second beam during an on-period of the DRX mode of the UE. 
 
     
     
       22. The method of  claim 16 , further comprising:
 ranking the beams of the first ordered set of beams based at least in part on a signal quality for each signal associated with the beams based at least in part on the feedback information, wherein generating the second ordered set of beams is based at least in part on ranking the beams. 
 
     
     
       23. The method of  claim 16 , further comprising:
 identifying an indication of signal quality based at least in part on receiving the feedback information, wherein generating the second ordered set of beams is based at least in part on identifying the indication of signal quality, wherein the feedback information includes received signal received power (RSRP), received signal received quality (RSRQ), a signal-to-noise ratio (SNR), a signal-to-interference-plus-noise ratio (SNIR), or a combination thereof. 
 
     
     
       24. The method of  claim 16 , further comprising:
 identifying a beam index of a beam of the first ordered set of beams selected by the UE to be used to communicate a wake-up signal based at least in part on the feedback information, wherein generating the second ordered set of beams is based at least in part on identifying the beam index selected by the UE. 
 
     
     
       25. The method of  claim 16 , wherein the set of reference signals comprises channel state information reference signals (CSI-RSs), demodulation reference signals (DMRSs), primary synchronization signals (PSSs), secondary synchronization signals (SSSs), or physical broadcast channel (PBCH) signals, or a combination thereof. 
     
     
       26. A method for wireless communication, comprising:
 transmitting a set of reference signals using a first ordered set of beams; 
 receiving feedback information from a user equipment (UE) operating in a discontinuous reception (DRX) mode, the feedback information based at least in part on the set of reference signals; 
 generating a second ordered set of beams for the set of reference signals that is different from the first ordered set of beams, the second ordered set of beams based at least in part on receiving the feedback information from the UE; 
 transmitting the set of reference signals using the second ordered set of beams; and 
 identifying a gap time between transmissions of the set of reference signals based at least in part on the feedback information indicating that the UE will change reception arrays to receive two adjacent signals of the set of reference signals, wherein transmitting the set of reference signals using the second ordered set of beams is based at least in part on identifying the gap time. 
 
     
     
       27. The method of  claim 16 , wherein the UE is in a connected discontinuous reception (C-DRX) mode. 
     
     
       28. The method of  claim 16 , wherein the feedback information is received during an on-period of a DRX cycle or during an off-period of the DRX cycle. 
     
     
       29. An apparatus for wireless communication, comprising:
 a processor, 
 memory in electronic communication with the processor; and 
 instructions stored in the memory and executable by the processor to cause the apparatus to:
 receive, by a user equipment (UE) operating in a discontinuous reception (DRX) mode, a set of reference signals in a first ordered set of beams, the first ordered set of beams comprising at least a first beam and a second beam to receive in a first order of a beam sweep; 
 identify a signal quality for a subset of reference signals received by the UE; 
 transmit feedback information to a base station based at least in part on identifying the signal quality for the subset of reference signals; and 
 receive the set of reference signals in a second ordered set of beams that is different from the first ordered set of beams, the second ordered set of beams based at least in part on transmitting the feedback information, the second ordered set of beams comprising at least the first beam and the second beam to receive in a different order of a later beam sweep. 
 
 
     
     
       30. An apparatus for wireless communication, comprising:
 a processor, 
 memory in electronic communication with the processor; and 
 instructions stored in the memory and executable by the processor to cause the apparatus to:
 transmit a set of reference signals in a beam sweep using a first ordered set of beams, the first ordered set of beams comprising at least a first beam and a second beam to transmit in a first order; 
 receive feedback information from a user equipment (UE) operating in a discontinuous reception (DRX) mode, the feedback information based at least in part on the set of reference signals; 
 generate a second ordered set of beams for the set of reference signals that is different from the first ordered set of beams, the second ordered set of beams based at least in part on receiving the feedback information from the UE; and 
 transmit the set of reference signals using the second ordered set of beams in a later beam sweep, the second ordered set of beams including the first beam and the second beam to transmit in a different order in the later beam sweep.